Cathedra

A semicircular or polygonal architectural termination of a church, traditionally located behind the principal altar or sanctuary. In many historic churches the apse contains the bishop’s cathedra, clergy seating, mosaics, frescoes, or other sacred art.

The principal church of a diocese, containing the cathedra, or official chair, of the diocesan bishop. The cathedral symbolizes the bishop’s teaching and pastoral office and serves as a central place for major diocesan liturgies.

Freedom from error in definitive teaching on faith or morals under the conditions established by Christ for the Church’s Magisterium. It belongs to the Church as a whole and is exercised in particular ways by the pope when speaking ex cathedra and by the college of bishops in union with him.